An Artificial Tongue Tells All About Toxins

Amnon Barzilai
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Amnon Barzilai

The well-equipped Israeli defense establishment may receive a significant addition by the end of the year - an artificial tongue.

Teams of scientists at three of Israel's universities - Hebrew University, Tel Aviv University and Ben-Gurion University - have overcome a hurdle that was considered impossible to conquer and developed an apparatus capable of identifying every kind of water contamination.

The research and development for building the two archetypes was largely financed by the Pentagon's Defense Advanced Research Projects Agency (DARPA). The next scientific challenge is to develop an artificial nose that could identify any kind of toxic gas in the air.

The scientific breakthroughs achieved in building the archetypes will serve as a basis for the operating systems. The impediment is money. Completing the projects requires an additional $10 million. The Defense Ministry, which invests billions of shekels to develop weapons for the battlefield, expressed admiration at the scientific achievement but made it clear that it has no budget for the additional expenses. Now the scientists are waiting for private investors who believe in the technologies' business potential to help develop a profitable commercial application.

On September 10, 2001, 24 hours before the terror attacks in the United States, a team of Israeli scientists was outlining the idea of developing an artificial tongue to senior Pentagon officials. The team was headed by biologist Prof. Shimshon Belkin, head of the environmental study unit at the Hebrew University in Jerusalem.

Prof. Belkin suggested genetically engineering bacteria to react to toxins in water and signal when the water was polluted and undrinkable. The Americans were enthusiastic about the idea, but thought it was relevant mainly for Israel.

"The next day everything changed," says Belkin. He envisions the day "when every Israel Defense Forces combat paramedic will have a device the size of a cell phone to identify toxins in the water."

An interdisciplinary group of scientists from the Health Ministry, the medical corps and TAU was added to Belkin's team.

"Unlike the Americans, we are good at carrying out multidisciplinary research in a relatively short time. With them it's cumbersome, slow and costly. This is why DARPA was ready to allocate $3.5 million for the Israeli project," says Prof. Yossi Shaham, head of TAU's nanotechnology department, who led the Tel Aviv team. "Shimshon gave me a call, and in two weeks we formulated the proposal. Colonel Boaz Tadmor of the medical corps was the liaison man in setting down the research subjects, and within a year we conducted our first successful experiment, headed by Lieutenant Colonel Patrick Bitan, the biologist in charge of water toxicity."

The Israeli scientists achieved a breakthrough when they managed to develop a device that can swiftly identify toxins in water.

"The existing identification systems are great in identifying toxins if they are acquainted ahead of time with the toxin's formula. But in the era of world terrorism, if someone develops a toxin whose formula is not known, or changes the attributes of an existing toxin, it would create endless possibilities with which the existing systems cannot cope," says Shaham.

Belkin developed a way to bypass the stage of identifying the type of toxin in the water. He claimed that in an emergency, one must focus on the fact that the water is toxic, to save time. The Jerusalem team he headed genetically engineered E. coli bacteria that exists in human intestines, so that they reacted to toxins in water by sending optical signals. The engineered bacteria react to toxins by means of light rays, similarly to fireflies. Shaham's team was in charge of the electronic engineering and developed the "platform" - the electronic chip on which the bacteria sit.

The biosensor weighs about five kilograms. At the Defense Ministry's directive, the next stage will be minimizing the apparatus to about half a square centimeter and weigh a few dozen grams.

Meanwhile, the team led by Dr. Robert Marks of Ben-Gurion University developed a system for identifying polluting elements. This team, consisting of scientists from BGU's biotechnology engineering department and the National Institute for Biotechnology in the Negev, used the engineered bacteria developed by Belkin's team, but instead of the electronic chip developed in TAU, they developed a fiberoptic platform for the bacteria.

The biosensor, comprising a fiber and bacteria, emits light when it comes into contact with toxic materials. The light's intensity increases with the potential toxicity.

The biosensor developed in Be'er Sheba is limited in its ability to identify the toxins to the number of optical fibers in the device. Marks' team developed two tools. One is easy to carry around and can identify five kinds of toxins. The other is immobile and heavy, but can identify more than 100 kinds of toxins. The Defense Ministry believes that the instruments are too large and the identification process is too slow.

A few weeks ago senior DARPA officials visited Ben-Gurion University and heard details of Marks' next plan - to develop a biopen, which will collect samples of all kinds of liquids (water, blood, urine, saliva) and identify toxins, bacteria and viruses on the basis of the developed system.

"Today people who test viral contamination are exposed to contagion. There is no device that can protect the scientist or whoever identifies the toxic substance completely. Even people who check for AIDS risk contagion. The biopen will be a closed environment. A drop of the liquid will be drawn into the pen and the optical fiber and sensor will identify the type of toxin in the liquid," says Marks.

"The only problem is money. We need $6 million - $2 million to develop the system and $4 million to turn it into a commercial application. Once we get the money, we'll need three years to complete the project. The problem is that the Defense Ministry has no money. Now we are waiting for the Americans' decision."

Immigrant scientists bring specialized know-how

The Defense Ministry contributes to developing systems for spotting water contamination by financing a new immigrant scientist in every team.

Professor Moni Magrisso, a biophysicist who immigrated from Bulgaria in 1998, joined Marks' team. Professor Yuri Rosenberg, a physicist who immigrated from Russia in 1999, joined Shaham's team. Magrisso, 48, developed the optical fiber enabling the determination of the water's toxicity level by light emission. Rosenberg, 67, developed a miniature magnetic pump for drawing water to test it.

"Everybody gains from our activity," says Yaakov Nagel of the Defense Ministry's R&D department. "We contribute to the absorption of immigrant scientists and thus help promote the projects. The Defense Ministry will benefit from the development of these projects."

The scientists' employment is financed by a joint fund formed five years ago by the defense, absorption and trade and industry ministries for immigrant scientists. The ministries set up a committee headed by Nagel and comprising among others MK Yuri Stern, one of the initiators of the project, and Dr. Leonid Diovitz, secretary of the Immigrant Scientists Association of Israel (ISAI). The committee's adviser, Colonel (res.) Reuven Eyal, is acting to locate immigrant scientists from Eastern Europe. The committee examines the possibility of employing the scientists in Defense Ministry projects. Most projects are in electrooptics, protection systems, lasers, engines, arms production and radar systems.

So far the fund for immigrant scientists has raised some NIS 40 million, from which the scientists' wages are paid - NIS 70 per hour, up to 180 hours a month. The defense establishment, which is the main beneficiary of the scientists' work, pays about half of the fund's budget. The fund pays the scientists' wages for three years, then considers their continued employment.

Dr. Yigal Klein, of the Defense Ministry's R&D department, is in charge of Magrisso and Rosenberg's activity. "Moni and Yuri came with a lot of specialized knowhow that contributes to our needs. The work involves professional risks. There is no guarantee that it will succeed. About 10 years ago we started looking for military applictions for miniature electrooptical technologies. Today we are willing to invest only in technologies that are not on the shelf and are challenging and long-term. We use existing infrastructures, seek out existing pockets of excellence and germinate innovative technologies that will enahnce the power of future arms systems and warfare," he says. (A.B.)